Sheath terminal for control cables

ABSTRACT

This terminal can be attached to an open cavity (27) of a dividing wall (60) by fixing one sheath end (26) of a control cable formed of a sheathed steel cable (7). The terminal includes a fixing body (1), a terminal body (6) and a retaining body (3) which can be attached to each other coaxially. In order to fix the terminal to the open cavity (27) the terminal further includes a stem (44), a spring (49) and a retaining pin (52) which can be moved by the user and has two working positions: a first position in which the stem (44) can slide in both directions in a fixing cavity (34); and a second position in which the stem (44) is immobilized once its free end (48) is fitted in a fixing orifice (61) of the dividing wall (60).

TECHNICAL FIELD OF THE INVENTION

The object of the invention is a sheath terminal for control cables,which is particularly applicable to control cables of the type generallyused in the automobile industry.

BACKGROUND OF THE INVENTION

Known in the art are numerous embodiments of control cables whichessentially consist in a control cable provided with a sheath in whichthe ends of the steel cable incorporate a respective steel cableterminal adapted for coupling thereof to an actuating control and to itsassociated mechanism, while the ends of the sheath incorporate arespective sheath terminal, one or both of which are attached, throughfixing means incorporated on the sheath terminal, to fixed pointssituated along the route of the steel-cable.

Fixing of one of the sheath terminals is frequently implemented on afixed point of the structure of the vehicle on which the steel cablepasses through a dividing wall. Passage of the steel cable through thedividing wall is implemented through a through-orifice which forms aclosed cavity or through a gap made on the edge of the dividing wallwhich forms an open cavity, said cavities being closed or open where thesheath terminal is fixed.

In those cases in which the sheath terminal is fixed to an open cavity,it is usual practice for the fixing means of the sheath terminal toinclude, along general lines, a tubular body to which is fixed the endof the sheath, which can be attached to the open cavity by means ofscrews or a body of elastic material. The main disadvantages of suchfixing means is that they require long assembly times for fitting thesheath terminal onto the automobile vehicle, which increases productioncosts, and/or a certain lack of reliability deriving from the fact that,under certain service conditions, for example when the sheath terminalfixing means are subjected to high mechanical stresses arising due tovehicle driving conditions, the sheath terminal can come out of the opencavity leaving the control cable out of service.

Document EP-A-627 570 (VOFA-WERK XAVIER VORBRUGGEN GmbH & Co. Kg,published on Dec. 7, 1994) describes a sheath terminal for controlcables which is attachable to a dividing wall. The sheath terminalcomprises a fixing body, a terminal body and a retaining body, which areall tubular and coaxially attached to each other, and means for theirattachment to a dividing wall, which include annular slots and elasticextensions inwardly extended. The sheath terminal has the drawback inthe performance of its fixing means, because once the terminal isattached to a fixing cavity in the dividing wall, if the sheath terminalneed to be removed from said retaining cavity for its maintenance or forrepairing the vehicle, the elastic nature of the fixing means makes itdifficult to carry out said removal.

DESCRIPTION OF THE INVENTION

A sheath terminal for control cables of original structure and operationis made known herein in order to provide a solution to the problemspresented by the known embodiments of sheath terminals such as thosedescribed above.

The sheath terminal of the invention comprises a tubular fixing body,terminal body and retaining body having open ends provided withrespective and complementary mutual coaxial attachment means so adaptedthat, once attached, the terminal body is fixed between the fixing bodyand the retaining body, and the steel cable of the control cable canslide freely in both directions through same, while the terminal bodyhas at one of its ends, the front end, fixing means for one sheath end,and the fixing body and the retaining body have respective andcomplementary fixing means of to an open cavity, characterized in thatsaid fixing means to comprise:

on one end of the fixing body, the rear end, a fixing groove in whichthere are one or more positioning planes adapted to receive with a snugfit corresponding positioning planes of the open cavity, and at itsother end, the front end, and running transversally, a fixing extensionon which, running longitudinally with respect to the fixing body, thereis a fixing cavity both ends of which, front and rear respectively, areopen and have two portions of different cross section and quadrangularoutline, the front of larger section and the rear of smaller section,respectively, which fixing extension has mounted transversally aretaining extension provided with an axial retaining orifice which leadsinto the fixing cavity;

on one of the ends of the retaining body, the front end, a radial fixingextension so adapted that, once the fixing, terminal and retainingbodies have been attached, it closes the front end of the fixing cavity;

a fixing stem which comprises a body having a cross section ofquadrangular outline and a thrust head adapted so that they can slidewith a snug fit in both directions through the rear and front portionsrespectively of the fixing cavity, the body of the fixing stem having aretaining orifice and length which permit one of its ends to projectfrom the fixing cavity;

a fixing spring fitted in the fixing cavity, which spring workspermanently under compression with one of its ends resting against theradial fixing extension of the retaining body and its other end againstthe thrust head of the fixing stem, all this so adapted that the body ofthe fixing stem tends to remain permanently to the exterior of thefixing cavity;

on the dividing wall, and at a relatively short distance from the opencavity, a fixing orifice through which the free end of the fixing stemcan slide with a snug fit;

a retaining pin fitted into the axial retaining orifice of the retainingextension and able to slide in both directions, the pin being so adaptedthat one of its ends, the exterior end, has means for holding by theuser, while its other end, the interior end, can be housed with a snugfit in the retaining orifice of the body of the fixing stem,immobilizing it, while the retaining pin and orifice of the retainingextension have respective and complementary positioning means whichpermit two working positions of the pin to be established:

a first position in which the fixing stem can slide in both directionswith its free end projecting from the fixing orifice and the fixingspring having its maximum length, in such a way that attachment of thefixing body to the open cavity leads to the dividing wall pressing uponthe free end of the stem and inserting it into the fixing cavity bysubmitting the spring to greater compression by reduction of its length,this until the fixing orifice of the dividing wall and the stem arefacing each-other, at which moment the fixing spring, by elasticreaction, drives the stem whose free end is housed in the fixingorifice; and

a second position in which the interior end of the retaining pin ishoused in the retaining orifice of the fixing stem, immobilizing it,leaving the position of the sheath terminal fixed in the open cavity dueto the combined action of the positioning planes of the open cavity andof the fixing body, and by the free end of the fixing stem housed in thefixing orifice of the dividing wall.

According to another characteristic of the sheath terminal of theinvention, the positioning means on the retaining pin comprise anannular positioning projection and, on the retaining orifice of theretaining extension two positioning grooves adapted to receive theannular projection with a snug fit.

According to another characteristic of the sheath terminal of theinvention, the coaxial coupling means comprise:

on the terminal body, an exterior, annular retaining projection;

on the front end of the fixing body, to the interior, a retaining cavityadapted to receive with a snug fit the annular retaining projection ofthe terminal body, and to the exterior, a plurality of couplingprojections; and

on the front end of the retaining body, to the interior, an annularretaining projection coinciding with that of the terminal body, and tothe exterior a plurality of coupling orifices adapted to receive with asnug fit the coupling projections of the fixing body.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings sheets of the present specification show the sheathterminal of the invention for control cables. In said drawings:

FIG. 1 is a perspective view of the components of the sheath terminal ofthe invention;

FIG. 2 is a perspective view of the sheath terminal of the invention assupplied ex-works;

FIG. 3 is a longitudinal-section view of the sheath terminal of theinvention;

FIG. 4 is a schematic section view of the fixing means of the sheathterminal of the invention as supplied ex-works;

FIGS. 5 and 6 are respective schematic section views of the fixing meansduring coupling of the sheath terminal of the invention into an opencavity;

FIG. 7 is a schematic section view of the fixing means once the sheathterminal of the invention has been attached to the open cavity.

DETAILED DESCRIPTION OF THE EXAMPLE OF EMBODIMENT

The sheath terminal of the invention for control cables described as anexample of embodiment, as shown in perspective view in FIG. 1, comprisesa fixing body 1, a terminal body 2, a retaining body 3, a retainer 4, apin 5 and a damper 6, all of generally tubular shape open at one oftheir ends and attachable to each other coaxially, so that, as shown insection in FIG. 3, a control cable steel cable 7 can slide freelythrough them in both directions. FIG. 3 shows how the terminal body 2 isfitted between the fixing 1 and retaining 3 bodies, with the retainer 4fitted between the terminal 2 and fixing 1 bodies, and the damper 6being fitted between the terminal 2 and retaining 3 bodies, they beingcoupled together through respective and complementary coupling means onthe fixing bodies 1, terminal 2 and retaining body 3. The pin 5 has onits front end 8 a thickened section of convex outline 9 which is fittedinto a semi-spherical cavity 10 made in the rear end 11 of the terminalbody 2, with the thickened section 9 and the semi-spherical cavity 10defining a knuckle joint coupling of the pin 5 and of the terminal body2 which, by elastic deformation of the retainer 4, permits the pin 5 torotate, adapting to any changes of direction of the steel cable 7 duringoperation of the control cable. The sheath terminal arrangementdescribed above is given solely by way of non-restrictive example, forit is understood that the composition of the terminal can be differentwithout this affecting the essential nature of the invention, with thesheath terminal comprising, for example, a terminal body and a retainingbody without damping or knuckle joint parts.

The coaxial coupling means comprise the parts detailed below. On therear end 11 of the terminal body 2, to the exterior, an annularretaining projection 12 shown in FIGS. 1 and 3. On the front end 13 ofthe fixing body 1, to the interior, a retaining cavity 14 shown in FIG.3, adapted to receive the retainer 4 with a snug fit through its frontend 15, the annular retaining projection 12 and the damper 6, and to theexterior three coupling projections 16, one of which is shown in FIGS. 1and 2. And, inside the front end 17 of the retaining body 3, an annularretaining spring 18, and to the exterior three coupling orifices 20shown in FIGS. 1 and 2, adapted to receive with a snug fit the couplingsprings 16 of the fixing body 1, as shown in FIG. 2. All this so adaptedthat when the front end 15 of the retainer 4, the annular retainingprojection 12 of the terminal body 2 and the damper 6 are in theretaining cavity 14 of the fixing body 1, as shown in FIG. 3, the fixingbody 1 is attached to the retaining body 3 by introducing theprojections 16 of the fixing body 1 into the corresponding orifices 20of the retaining body 3, following double elastic deformation of thelatter, as shown in FIG. 2, leaving the terminal body 2 subjected tocompression between the front end 15 of the retainer 4 and the damper 6.In this position, the retainer 4 by its rear end 21 and the pin 5 by itsrear end 22 project from the rear end 23 of the fixing body 1, while thefront end 24 of the terminal body 2 projects with respect to the frontend 17 of the retaining body 3.

FIG. 3 shows in section how the front end 24 of the terminal body 2includes an axial orifice 25 adapted to receive with a snug fit andsecure one control cable sheath end 26.

FIG. 1 shows how the sheath terminal of the invention can be coupled toan open cavity 27 made in a dividing wall 60, a-metal plate for example,the cavity 27 having a generally U-shaped outline in which are definedtwo lateral positioning planes 28, which form a certainexterior-oriented angularity, attached by a linking positioning plane29.

For attachment thereof to the open cavity 27, the sheath terminal of theinvention includes fixing means which will be described below.

The rear end 23 of the fixing body 1 has a fixing groove 30, shown inFIGS. 1, 2 and 3, in which three positioning planes are defined, twolateral 31 and one linking 32, coinciding with the lateral positioningplanes 28 and linking plane 29, respectively, of the open cavity 27,with the fixing groove 30 being of sufficient size to receive the opencavity 27 with a snug fit, while on its front end 13 and mountedtransversally, the fixing body has a fixing extension 33, shown insection in FIG. 4, on which there is a fixing cavity 34 whose front 35and rear 36 ends, respectively, are open, the cavity 34 having twosection, the front 38 of larger section and rear 38, respectively,linked to define a step 39. Transversally mounted with respect to thefixing extension 33, there is a retaining extension 40 in which there isan axial retaining orifice 41 which leads into the fixing cavity 34,while the orifice 41 has two positioning grooves, first 42 and second43, respectively, each situated at a relatively short distance from theother.

The front end 17 of the retaining body 3 has a radial fixing extension57 so adapted that, as shown in FIGS. 2 and 4, once the fixing 1 andretaining 3 bodies have been attached, it closes the front end 35 of thefixing cavity 34.

FIG. 4 shows how the fixing cavity 34 has fitted in it a fixing stem 44in which there is a body 45 of quadrangular cross section and a thrusthead 46, both so adapted as to slide with a snug fit through the rear 38and front 37 portions, respectively, of the fixing cavity 34 in whichthe step 39 acts as a stop for sliding of the stem 44, while the body 45has running transversally a retaining orifice 47 and is of lengthdimensions such that its free end 48 can&project from the rear portion38.

In the fixing cavity 34 there is a fixing spring 49 which workspermanently under compression and which, as shown in FIG. 4, rests byone of its ends, the front end 50, against the radial fixing extension57 of the retaining body 3, while its other end, the rear end 51, restsagainst the thrust head 46 of the fixing stem 44.

FIG. 4 shows how, fitted snugly in the axial retaining orifice 41, thereis a retaining pin 52 of circular cross section which can slide in bothdirections, which retaining pin 52 has on its interior end 53 a conicalfinish 54 adapted for insertion with a snug fit in the retaining orifice47 of the fixing stem 44, on its central portion 55 an annularpositioning projection 56 adapted for housing with a snug fit in thefirst 42 and second 43 positioning grooves, fixing the position of thepin 52 by establishing two working positions, first and secondrespectively, and on its exterior end 58 a head 59 which permits theuser to hold the pin 52.

The sheath terminal is supplied ex-works as shown in FIGS. 2, 3 and 4,so that in this position, as shown in FIG. 4, the retaining pin 52 hasits positioning projection 56 in the first positioning groove 42,thereby establishing a first working position of the pin 52 in which thefree end 48 of the fixing stem 44 projects from the fixing cavity 34.

The functioning of the sheath terminal of the invention for controlcables which is described as an example of embodiment is extraordinarilysimple and is outlined below.

Fitting of the sheath terminal in the cavity 27 in the dividing wall 60simply requires carrying out of the following operations:

firstly, the sheath terminal is so fitted that, with the lateral 28, 31and linking 29, 32 planes coinciding, which planes are includedrespectively and complementarily in the open cavity 27 and the fixingbody 1, the dividing wall 60 is arranged in the fixing groove 30, insuch a way that, as shown in FIG. 5, the dividing wall 60 itself, bypressing on the free end 48 of the stem 44, introduces the latterfurther into the fixing cavity 34 by submitting the fixing spring 49 togreater compression by shortening its length, and this continues until afixing orifice 61 in the dividing wall 60 and the free end 48 of thestem 44 are left facing each other, at which moment, as shown in FIG. 6,by elastic reaction of the fixing spring 49 the free end 48 isintroduced into the fixing orifice 61; and,

the retaining pin 52 is then moved until its positioning projection 56is housed in the second positioning groove 43 as shown in FIG. 7, inwhich position the interior end 53 of the pin 52 is introduced into theretaining orifice 47 of the stem 44, immobilizing it.

The combined action of the lateral 28, 31 and linking 29, 32 positioningplanes and of orifice 61 and stem 44 fix in highly reliable fashion theposition of the sheath terminal in the dividing wall 60.

Where vehicle maintenance or repair needs require that the sheathterminal of the invention be withdrawn from the open cavity 27, the usersimply has to move the retaining pin 52 in such a way that itspositioning projection 56 is housed in the first positioning groove 42,releasing the stem 44, and then, using any suitable tool the free end 48of the fixing stem 44 must be pushed and introduced into the fixingcavity 34, while the sheath terminal of the invention which is in theinitial position described above is withdrawn from the open cavity 27.

What is claimed is:
 1. A sheath terminal for a control cable which canbe attached to an open cavity (27) in a dividing wall (60), fixing onesteel cable (7) sheath end (26) of the control cable, characterized inthat the terminal includes a tubular fixing body (1), terminal body (2)and retaining body (3) having open ends provided with respective andcomplementary mutual coaxial attachment means so adapted that, onceattached, the terminal body (2) is fixed between the fixing (1) andretaining (3) bodies and the steel cable (7) of the control cable canslide freely in both directions through same, while the terminal body(2) has at one of its ends, the front end (24), fixing means for onesheath end (26), and the fixing and retaining bodies have respective andcomplementary means of fixing to an open cavity (27), which fixing meanscomprise:on one end of the fixing body (1), a rear end (23), a fixinggroove (30) in which there are one or more positioning planes (31, 32)adapted to receive with a snug fit corresponding positioning planes (28,29) of the open cavity (27), and at its other end, a front end (13), andrunning transversally, a fixing extension (33) on which, runninglongitudinally with respect to the fixing body (1), there is a fixingcavity (34) both ends of which, front (35) and rear (36), respectively,are open and have two portions of different cross section andquadrangular outline, the front (37) of larger section and the rear (38)of smaller section, respectively, which fixing extension (33) hasmounted transversally a retaining extension (40) provided with an axialretaining orifice (41) which leads into the fixing cavity (34); on oneof the ends of the retaining body (3), the front end (17), a radialfixing extension (57) so adapted that, once the fixing (1), terminal (2)and retaining (3) bodies have been attached, it closes the front end(35) of the fixing cavity (34); a fixing stem (44) which comprises abody (45) having a cross section of quadrangular outline and a thrusthead (46) adapted so that they can slide with a snug fit in bothdirections through the rear (38) and front (37) portions respectively ofthe fixing cavity (34), the body (45) of the fixing stem (44) having aretaining orifice (47) and length which permit its free end (48) toproject from the fixing cavity (34); a fixing spring (49) fitted in thefixing cavity (34), which spring works permanently under compressionwith one of its ends resting against the radial fixing extension (57) ofthe retaining body (3) and its other end against the thrust head (46) ofthe fixing stem (44), all this so adapted that the body (45) of thefixing stem (44) tends to remain permanently to the exterior of thefixing cavity (34); on the dividing wall (60), and at a relatively shortdistance from the open cavity (27), a fixing orifice (61) through whichthe free end (48) of the fixing stem (44) can slide with a snug fit; aretaining pin (52) fitted into the axial retaining cavity (41) of theretaining extension (40) and able to slide in both directions, the pin(52) being so adapted that one of its ends, an exterior end (58), hasmeans for holding (59) by the user, while its other end, an interior end(53), can be housed with a snug fit in the retaining orifice (47) of thebody (45) of the fixing stem (44), while the retaining pin (52) andorifice (41) of the retaining extension (40) have respective andcomplementary positioning means which permit two working positions ofthe pin (52) to be established: a first position in which the fixingstem (44) can slide in both directions with its free end (48) projectingfrom the fixing cavity (34) and the fixing spring (49) having itsmaximum length, in such a way that attachment of the fixing body (1) tothe open cavity (27) leads to the dividing wall (60) pressing upon thefree end (48) of the stem (44) and inserting it into the fixing cavity(34) by submitting the fixing spring (49) to greater compression byreduction of its length, this until the fixing orifice (61) of thediving wall (60) and the stem (44) are facing each other, at whichmoment the fixing spring (49), by elastic reaction, drives the stem (44)whose free end (48) is housed in the fixing orifice (61); and a secondposition in which the interior end (53) of the retaining pin (52) ishoused in the retaining orifice (47) of the fixing stem (44),immobilizing it, leaving the position of the sheath terminal fixed inthe open cavity (27) due to the combined action of the positioningplanes (28, 29, 31, 32) of the open cavity (27) and of the fixing body(1), and by the free end (48) of the fixing stem (44) housed in thefixing orifice (61) of the dividing wall (60).
 2. A sheath terminal asclaimed in claim 1, characterized in that the positioning means on theretaining pin (52) comprise an annular positioning projection (56) and,on the retaining orifice (41) of the retaining extension (40) twopositioning grooves (42, 43) adapted to receive the annular projection(56) with a snug fit.
 3. A sheath terminal as claimed in claim 1 or 2,characterized in that the coaxial coupling means comprise:on theterminal body (2), an exterior, annular retaining projection (12); onthe front end (13) of the fixing body (1), to the interior, a retainingcavity (14) adapted to receive with a snug fit the annular retainingprojection (12) of the terminal body (2), and to the exterior, aplurality of coupling projections (16); and on the front end (17) of theretaining body (3), to the interior, an annular retaining projection(18) coinciding with that of the terminal body (2), and to the exteriora plurality of coupling orifices (20) adapted to receive with a snug fitthe coupling projections (16) of the fixing body (1).